Why the mortality peak?
Epidemics of certain diseases, such as bubonic plague and cholera, can cause very sudden and steep rises in mortality levels, but neither of these can explain the catastrophe at Deane, since bubonic plague disappeared in England during the 17th century, and cholera did not reach British shores until the 19th century.
'The scale of disaster that harvest failure can bring is only too evident in developing countries today ...'
Other common killer diseases at this time were influenza, dysentery and smallpox. The problem here is that the mortality crisis at Deane persisted for several years, whereas outbreaks of such illnesses almost never last as long as this.
Another possibility is famine. The scale of disaster that harvest failure can bring is only too evident in developing countries today, and the position was no different in 18th-century Britain. Such a hypothesis would help to explain the simultaneous fall in the number of births that the Deane parish records indicate, since women who are starving are less likely to conceive and less likely to give birth to healthy babies. Could it be that the people of Deane were simply dying of hunger?